Process of treating refractory ores containing iron sulfids.



flea/ll whom it may concern:

ence therein of iron and that it nnrra LESLIE VERO ATKINSON. OF

1. R. REFRACTORY ORE SYN GARSHALTON, ENGLAND, ASSTGNOR TO THE IJIUATE LIMITED, OF LONDON, ENGLAND.

snares Paar crate.

PROCESS OFTREATING REFRACTORYORES CONTAINING IRON SULFIDS. I

Specification of Letters Pateht' Patented July 3. 1906.

Application and July 6, 1905. Serial No. 268.530.

Containing Iron Sulfids, of which the following is a specification.

This invention relates to so-called refractory ores, which contain iron sulfids, and is a wet process for the recovery from such ores of iron, gold, silver, copper, cobalt, and arsenic. .It is designed to purif and prepare the ores which contain iron in arge percentage, and I have found that the refractory character of the ores is defined by the pres is possible to closely recover the metals mixed therewith treIneheat being necessary to remove the' said iron, which will thus leave other metals" in the ore unchanged. It has, moreover, been found that the recovery of the said metals from the ores can be well carried out by known processes so long as the iron has been removed from the said ores at a merely gentle 'heat, so that the process of extraction can be made payable;

My method is after having broken up the ore to a certain fineness and by having concentrated them closely to raise the value of the metal contents to sulfate the iron in the ores by means of a dense steam atmosphere from which the free admission of atmospheric air is excluded. This may be done at a temperature of about 350 Fahrenheit. As the generation of the sulfate from the sulfid proceeds more quickly under slight pressure of steam and at a greater heat,

this may be raised to a temperature of about Fahrenheit, which is the limit of the temperature required. a

I am aware that the production of iron and other sulfates from ores is not novel; but the excess temperature usually used to make the gradually copper sulfid into a sulfate will produce at the same time an iron peroxid, so that it cannot be removed from the ore and will serve to spoil the result.- Under these conditions of temperature sulfur and arsenic will volatilize and may, with the waste steam, be allowed to escape to a suitable condenser for the collection of the arsenic. When the arsenic has been eliminated, the temperature may be raised another 50 Fahrenheit, and during this period a grinder in the furnace is started to still further reduce the ore to a liner grade and to still further operate upon the iron present. This point may be tested during calcination to determine the necessary,

fineness of the ore and of iron to be sulfated.

. The operation in the conversion of sulfid of iron to sulfate may take from two to four hours, and about forty minutes is required before the admission of the steam to get the necessarytemperaturc in the furnace. Iron sulfate readily dissolves in boiling water and in a somewhat slower degree in hot or even cold Water; Therefore Iprefer to use a steam-coil in order to raise the water to or near boiling-point.

the necessary amount At this point of iron sulfation the ore is disupon the removal of the iron without any excharged from the first furnace to the vats, filters, or other vessels in which the iron sulfate is removed from the ore by means of boiling Water. It is preferable that the ore discharge shall be under cover, as too much air is not desirable; but the use of covered trucks which will exclude atmosphere will answer the purpose. The balance of the ore when the sulfate of iron is eliminated may now be treated in any usual fashion by the application of an electric current, by chlorination, or otherwise, for the collection of silver, gold, or copper, it being found that these metals are lying quite hpart and distinct from each other in the ore after the elimination of the iron.

Having now described my invention, what I claim, and desire to secure by Letters Pat ent, is

1. A process for treating refractory ores containing iron sulfids consisting of forming a preliminary sulfate of iron from the sulfids in the ore,before other metals present are chemically changed, and then removing the iron sulfate from the ore by dissolution in a liquid.

2. A .process forv treating refractory ores containing iron sulfide consisting of forming a sulfate of iron undr a steam atmos here with a gentle heat, thus l aving the ot 1er metals present untouched and then removing the iron sulfate from the ore by boiling Water.

3. A process for treating refractory ores containing iron sulfide and copper arsenic consisting of forming a sulfate of iron under a steam-pressure at a temperature of not less than 350 Fahrenheit and not more than 750 Fahrenheit, this being a ehfhoiently gen: the temperature not to make a copper or other metal sulfate, collecting the mee'nious ases as a product, and then removing the siilfete of iron from the ore by boiling Water.

4. A process for treating refractory gold, silver and copper bearing ores containing iron sulfide consistin of removing the iron by sul-- fetion and a so ution in boiling water from gold, silver, or copper ores, and thereafter using oyenid to recover any of the other metals of the ores.

5. In. a process for treating refractory ores conteining iron sulfide the-reduction by grindihg of the ores containing a sulfid of iron, C011", [5-

oentratihg the ores, and forming a sulfate of iron from the snlfid by an atmosphere of steam to render the sulfate soluble in boiling Water for its removal from the ore.

In testimony whereof I have signed my 20 name to this specification in the presence of two subscribin witnesses.-

LE LIE VE RO ATKINSON.

Witnesses:

CHARLES CARTER, H. W1 JAtmsmw 

